The present invention relates in general to packages for storing optical fibers. The invention relates in particular to a sterilizable package for storing and dispensing optical fiber used for delivering laser energy from a laser to a treatment site in medical laser applications.
In many applications of lasers in medical and surgical treatment, laser radiation is delivered from a laser via an optical fiber to a site being treated. Such treatment frequently involves an optical fiber penetrating a human body via an existing aperture or via an incision in the body to allow a site inside the body to be accessed. Examples of such treatments are in heart treatments, such as angioplasty and the like, and in transurethral treatment of prostate gland conditions.
An optical fiber used in such an application can have a length of up to 5 meters (m) or longer. Such an optical fiber is fragile and is difficult to store. Storage difficulty is due, among other factors, to a spring-like quality of the fiber which imparts a resistance to coiling the fiber. This requires that some means be provided for retaining the fiber in a coiled form.
A package for storing and dispensing such an optical fiber preferably protects the entire length of the fiber when the fiber is not in use, and protects an unused portion of the fiber when less than the entire length of the fiber is not in use. Preferably, it should be possible to withdraw the fiber from, or insert the fiber into, the package at both the end of the fiber that is connected to the laser and at the end of the fiber that delivers the radiation. Because of medical usage of the fiber, in particular in applications where body penetration is necessary, the optical fiber package and the optical fiber contained therein should be easily sterilizable.
The present invention is directed to a package for storing a continuous length of optical fiber. The package is configured for allowing the stored length of the optical fiber to be withdrawn from the package for use and replaced after use.
In one aspect, a package in accordance with the present invention includes two mating members. The mating members are configured such that, when joined, they form an annular package including separate inside and outside concentric annular chambers. A circumferential slit around inside and outside edges of the annular package allows access to respectively the inside and outside chambers. Two fiber-guides are provided, one engaging the inside edge and the other engaging the outside edge of the package. Each of the fiber guides is configured such that it can slide around the edge that it engages. An aperture in adjacent walls of the inner and outer chambers allows passage of the optical fiber from one chamber to the other. The continuous length of optical fiber is stored in the package with one portion of the fiber coiled in the inside chamber and another portion coiled in the outside chamber. The stored portions are linked via the apertures in the chamber walls. One end of the optical fiber extends through the inner-edge slit and through the inner-edge fiber-guide, the other end of extends through the outer-edge slit and the outer edge fiber-guide. In one preferred mode of operating the inventive package, optical fiber can be withdrawn from or replaced in either chamber by sliding the corresponding fiber guide away from or toward the end of the optical fiber extending therethrough.
In another aspect the chamber walls of the inventive package include a plurality of apertures arranged to allow circulation of one or more of fluids and gases in the chambers for sterilizing the chambers and the optical fiber stored therein. Preferably, the apertures are circumferentially and about equally spaced apart around the chamber walls.
In one preferred embodiment, the inventive package includes first and second annular mating members. Each of the mating members includes inner and outer concentric raised portions having a separating portion therebetween. The first and second raised portions are bounded on a side thereof opposite the separating portion by respectively an inner edge portion and an outer edge portion. The first and second mating members are fixedly joined at the separating portions thereof with corresponding ones of said edge portions in close proximity to each other such that the first and second raised portions form the inner and outer concentric chambers. The edge portions in close proximity form inner and outer edges of the package each having a slit extending completely therearound. The inner-edge and outer-edge slits allow access for the optical fiber to respectively the inner and outer chambers.